Parameter: λ13 Identified

Algebraic Equations:

σ12λ1323

Instrumental Variable:

2 | {}

Parameter: λ34 Identified

Algebraic Equations:

σ13λ3414

Instrumental Variable:

1 | {}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω12 Identified

Algebraic Equations:

1212

Parameter: ω13 Identified

Algebraic Equations:

12σ1311σ2312ω13

Parameter: ω22 Identified

Algebraic Equations:

2222

Parameter: ω24 Identified

Algebraic Equations:

σ14σ2313σ2413ω24

Parameter: ω33 Identified

Algebraic Equations:

12σ13σ2311σ232122σ33122ω33

Parameter: ω34 Identified

Algebraic Equations:

σ14σ3313σ3413ω34

Parameter: ω44 Identified

Algebraic Equations:

142σ33+2σ13σ14σ34132σ44132ω44

Total Effect of X1 on X4: λ13λ34 Identified

Each Parameter Identified

Vanishing Ideal

Zero Vanishing Ideal